Microsoft is aiming to release the next version of its desktop operating system, now dubbed Windows 7, in 2010. Few details are yet available regarding the forthcoming platform but reports suggest it may now be a major release instead of the interim update previously planned.

The next version of the Windows client was formerly called Vienna and was intended to be a minor upgrade for Windows Vista. At a recent global sales conference in Florida, Microsoft disclosed it is gearing up for a full-scale upgrade in three years’ time, barring any setbacks during development.

“We are scoping development of Windows 7 to an approximately three-year timeframe, with the specific release date ultimately determined by meeting our quality bar,” Microsoft said.

Windows 7 will ship in both 32bit and 64bit editions, a reversal of Microsoft’s earlier position that stipulated that Windows versions beyond Vista would be 64bit only. It is believed the release will have a new version of Windows Explorer inspired by the Ribbon user interface introduced in the Office 2007 productivity suite.

Paul Dawson of consultant firm Conchango said that, given the development timescale and the name, it should be assumed that Windows 7 will be a major release. He added that it will likely pick up where Vista left off, in areas that Microsoft still feels are weak compared with rivals.

“I think we can expect to see Microsoft address ease of use. Security will be an ongoing concern, plus better management of personal data and better sharing of information across multiple devices,” Dawson said.

The three-year timescale means that many firms may have only just moved to Vista by the time Windows 7 is released, judging by recent research into customer migration plans by Dell. However, Dawson said that Microsoft has to keep moving to stay ahead of the competition.

“I suspect migration from Vista to Windows 7 will, in any case, be much easier than from XP to Vista,” Dawson added.

Meanwhile, a backlash against Vista seems to be growing, with Acer president Gianfranco Lanci reportedly saying the platform has had the least impact on PC sales of any Windows launch, is riddled with problems, and that the whole industry is disappointed with the new operating system.

Many PC vendors have continued to offer Windows XP, citing demand from buyers as the reason. Microsoft has recently upgraded its estimates for Windows XP sales for the rest of the year.